These are ectopic pregnancies located outside the endometrial cavity of the uterus but not within the fallopian tubes. While they are relatively rare accounting for about 5% of all ectopic pregnancies, they are currently witnessing an overall increase in incidence. They are also disproportionately associated with far more deaths and significantly more complications than tubal pregnancies. This is because they are often detected late, and possess a propensity to bleed more, luckily they are quite rare. They are classified based on their location into interstitial, cornual, angular, ovarian, abdominal, cervical, caesarean scar and intramural pregnancies.
Even though the interstitial pregnancy occur in the interstitial part of the fallopian tube and may be referred to as a form of tubal pregnancy, for the purpose of our discussion, it will be described as part of the non-tubal ectopic pregnancies, because it occurs in that part of the uterus where the fallopian tube enters the uterus, close to the location of the angular pregnancy, with both having some similar features at presentation. Not surprisingly, because this region is referred to anatomically as the cornual part of the uterus, all three, i.e. interstitial, angular and cornual pregnancies are often used interchangeably by some specialist though strictly speaking these are separate entities.
As the name implies, ovarian pregnancy refers to an ectopic pregnancy located in the ovary, while the abdominal, cervical, and caesarean scar pregnancies refer to ectopic pregnancies located in the abdominal cavity, cervix and caesarean section scar respectively. Intramural pregnancy on the other hand refers to an ectopic pregnancy embedded within the muscle mass of the uterus (womb) sequel to a defect in the uterine wall during a previous surgery such as a myomectomy or a D & C.
Some of the non-tubal ectopic pregnancies such as the ovarian and interstitial ectopic pregnancies share similar risk factors with tubal pregnancies. They include a history of a previous ectopic pregnancy, pelvic infections, and the presence of an intrauterine contraceptive device (IUCD) as well as the use of IVF in ART cycles. Others however have distinct risk factors.
Although, presentations are similar to that of tubal pregnancies, here, a more variable period of amenorrhea, pregnancy symptoms and vaginal bleeding, may be observed depending on the types of non-tubal ectopic pregnancies. In general, presentation is late and once early diagnosis is missed, there is a tendency for non-tubal ectopic pregnancies to present with a severe acute onset of generalized abdominal pain, associated with a greater degree of intra-abdominal bleeding as well as a greater risk of complications and death compared to tubal pregnancies.
These are similar to those of tubal ectopic pregnancies (see Tubal ectopic pregnancy :). Others are
1. Tubal ectopic pregnancy
2. Normal pregnancy with a live fetus
3. Normal pregnancy with a dead fetus
Generally, investigations and diagnosis enlist steps similar to that used in the management of tubal pregnancies and include the use of various blood tests, ultrasound scan and diagnostic laparoscopy to determine the location of pregnancy (see TUBAL ECTOPIC PREGNANCY: DIAGNOSIS AND INVESTIGATIONS). While it may be difficult to differentiate them from tubal pregnancies at presentation, a detailed clinical history, a thorough clinical examination and proper investigations and a high index of suspicion are often times required to make a diagnosis of non tubal ectopic pregnancy prior to rupture while many however are detected only after rupture during surgery (during emergency laparatomy)
Though specific management often defers based on the type of non-tubal ectopic pregnancy and the clinical stability of the patient at presentation, management is usually by either medical or surgical, similar to tubal pregnancies. Rarely, Conservative management may be reserved for very carefully selected cases under very close and strict supervision. Clinically stable patients are usually offered medical means of management and in some instances a combination of both medical and surgical means, employing procedures aimed at terminating the pregnancy, reducing the risk of rupture and preventing excessive bleeding usually associated with these types of ectopic pregnancies. In acute emergency, surgery is the main stay of management aimed at reducing the blood loss usually associated with these types of ectopic pregnancies. Hysterectomy is a well known complication of these types of ectopic pregnancy usually done as a last resort to stem excessive blood loss. In all instances, non-tubal ectopic pregnancies should be managed in tertiary health institutions where multidisciplinary specialists are present and blood products are available for transfusion.
Although these are similar to those of tubal pregnancies, complications here are generally worse and associated with a higher risk of bleeding and an increased risk of hysterectomy. There is a higher risk of death compared to tubal pregnancies and as such they should be managed in tertiary health institutions where there are multiple specialists and adequate supply of blood.
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